1. Field of the Invention
The present invention relates to a system and a method for power control. More particularly, the present invention relates to a system and a method for power control by controlling a power to be switched on or off.
2. Description of Related Art
As the rapid development of science and technology, electronics have been increasingly prevailing. Portable electronics, such as notebook computers, personal digital assistants (PDAs) are the most favorite ones among the users, due to the features of being light, thin, short, and small and having multiple functions.
As for the portable electronic products, the power supply is an important part. In order to provide the portable electronic products with a battery having a long endurance and save the consumption of the battery, a rechargeable lithium battery is generally used as a source for the power supply in the conventional art. When the power of the lithium battery is not sufficient, it only needs to connect the electronic product to a transformer, which can charge the lithium battery.
However, the current transformers available on the market do not have the functions of automatically controlling the power on/off of the power thereof. That is to say, when the lithium battery has already been charged completely, the transformer will continuously supply the power. Even when the electronic product is powered off, the transformer still continuously runs, and thus the power is continuously consumed. As a result, the power is continuously consumed and the energy is wasted by the transformer, and thus leading to the overheating of the transformer and shortened service life of the transformer.
In order to solve the problems, the conventional art has proposed a set of solutions, that is, adding a manual switch in front of the transformer. When the user does not need the transformer to supply the power, he/she manually switches off the transformer, as described in ROC Patent Application No. M259392. However, the above method can only tackle the problem on the surface, not at the root. Each time when powering off the transformer, the user must manually turn off the switch of the transformer personally, which is not only considerably inconvenient for the user, but the situations that the user forgets to turn off the switch of the transformer also occurs, and thus, the switch disposed for the transformer are almost non-existed.
In view of above, all the relevant manufactures of the portable electronic products are anxious to seek for proper solutions to overcome the above problems.